This invention relates to a printer, especially to one in which the print position can move vertically to print a super-script character or a sub-script character.
It is widely known that a super-script character or a sub-script character (e.g. x.sup.2, A.sub.max) is printed by a printer in which either the printing head or printing paper is moved vertically.
When a return key is pressed on a typewriter or a return code is sent to a printer, the printing head moves both down (or the paper is fed upward) by a preset line feed amount and to a preset left margin position.
However, when the return key is pressed with the print position in a nonstandard row position to print a superscript or sub-script character, the print position moves down by the preset line feed amount from the abnormal position. If printing is continued on the new line, the vertical distance between the printed lines is different from the normal gap. Also, in case of a text data editing after a line feed code is entered in a text data in order to print a super-script or a sub-script character, the operator sometimes forgets to place the restore code in the text data in order to return the printing head to the predetermined standard row position.
Consequently, it causes a badly printed document having an irregularity in line spacings and deterioration in printing quality.